Did Muslims believe that anyone who died in battle for Islam would go to paradise?

Religious beliefs and convictions vary by the individual and are not monolithic. Muslims, as in all world religions, have opinions and theological ideas as to the application of violence and concept of being a martyr to a cause. The idea of dying for cause and being rewarded in the afterlife is to be found not only in Abrahamic faiths but in others also. Another problem is the the ideas of martyrdom and dying for ones nation or state are also manipulated for political and personal gains by perversion and distortion of religion.